The present invention is directed to an electrostatic powder-coating gun generally, and in particular to a gun having a gun barrel, the gun comprising a powder duct which is connected to a supply conduit for a powder-air-mixture and arranged along the longitudinal axis of the gun barrel towards the work to be coated and terminating in a mouth; a high-voltage generator connected to a power supply line; and a high-voltage electrode which is located protruding beyond the mouth of the powder duct towards the work and connected to the high-voltage generator via a conductor. Electrostatic powder-coating guns of such construction have been known for a long time and various designs are commercially available.
In general, with such known coating guns the powder-air-mixture is fed through the grip or adjacent the grip, the powder duct extending through the entire length of the gun barrel. The high-voltage generator is located in parallel with the powder duct either within or on the grip or within or on the gun barrel. However, this results in an elongated flow path for the powder-air-mixture inside the gun so that the air for feeding the powder requires a high pressure in order to overcome the flow resistance within the gun. Also, the flow of powder through the elongated powder duct results in a comparatively high wear of parts due to abrasion. Finally, the arrangement of powder duct and high-voltage generator in side-by-side relationship requires that either the grip or the gun barrel must have relatively large dimensions.